Why can MELF resistors resist sulfuration?
Sulfur in the air – resistor killer
Chip resistor contains silver(Ag) in its electrode structure. When there is a large amount of sulfur in the air, the silver tends to react with it and becomes silver sulfides(Ag2S or Ag2SO4), and the silver loses its conductivity. As a result, the resistance value gradually increases and eventually becomes an open circuit. Below is the diagram of the internal structure of a chip resistor:
The Best solution for anti-sulfuration:
MELF resistor - there is no silver(Ag) content in the production process and raw materials, so there will be no sulfuration.